1. Field of the Invention
The present invention relates to a method for transmitting data. In particular, this invention relates to a method for transmitting data that uses a plurality of transmitters to transmit their data to a receiver at different times within a transmission interval.
2. Description of the Related Art
As the car electronic technology has been developed, the tire pressure monitoring system (TPMS) becomes a popular device for the car. TPMS can immediately monitor and display the tire pressure and temperature. When the tire pressure is too high or too low, or the tire temperature is too high, TPMS informs the driver by a sound or light signal. Thus, the car is always assured to operate with correct tire pressure status.
The traditional TPMS uses a plurality of tire pressure transmitters to transmit tire pressure data to a remote receiver periodically during specific transmission intervals. Therefore, the driver obtains real time tire status, and danger is avoided.
In the traditional TPMS each transmitter usually transmits its tire pressure data at a predetermined transmission time within each transmission interval, the transmission time being different for each transmitter. Because the basic oscillation times of the tire pressure transmitters may differ slightly, the transmission intervals and the transmission times for each of the tire pressure transmitters may vary slightly over time.
Thus, after continuous operation of the TPMS, the transmitting times of the transmitters may drift in such a way that two transmitters repeatedly transmit their tire pressure data at the same time. The tire pressure receiver cannot simultaneously receive data from different transmitters and thus tire pressure data can be lost.